DOES THE HDK SUSPENSION K-MEMBER HANDLE BETTER THAN A T-BAR SUSPENSION?

It isn't easy in a new car let alone something that's 50 years old. And I would love it even more for them to come jump in the car at any of the events I do. You will be holding on to something and pressing a brake pedal that doesn't exist. I don't care how many hills or curvy roads you have near your home. You aren't driving your car like you will on an autocross
Yes most most people don't and maybe can't appreciate the difference between spirited street driving and autocross, nor between highway driving and being on a road course or other closed track.

Fortunately at least a fair number of participants in this thread actually do have that experience and so do know. I'd say more than typical in these sort of threads. :)

As to your first point snipped above, I'll say my limited experience with autocrossing newer sports cars has been that in the last decade or two they have really made it easier to do well. It is harder to compete in the national classes available with an older car without some modification and body trimming. ESP, CP, and CAM-T are the choices in SCCA.

FWIW, I would love to get on a AutoX course. I've looked, and if memory serves I couldn't even find one in Seattle.
Looks like they are right across the narrows from Seattle.
https://nwr-scca.org/event-schedule/
I think Randy Pobst wrote an article saying that, too. And he is one of the top road course guys, so I won't argue with that assessment.
Yes he did, although maybe not as an absolute, but rather as a general observation. It had to do with the need for precision, and perhaps the discipline to control the speed rather than seek the high speed.